Using regeneration power (such as solar power) as electric power source is suitable for environmental protection and matches the requirement of power saving. However, many regeneration power systems can not be operated all day long. They are not suitable for the systems operated whole day. Thus it is needed to resolve this problem for the regeneration power systems.
Besides, in IEEE 802.3af, Ethernet data wire or standby wires are used to supply power to Ethernet devices without using adapters.
For the devices based on the IEEE 802.3af, such as IP telephones, wireless feeding points with power level smaller than 12.95 W, a CAT-5is used for power supply. This causes that the wall type transformer is not used and new devices are developed. These devices are integrated with data and power interfaces so that it is compatible with other Ethernet devices of 10, 100 or 1000 Mbps. The use of IEEE 802.3af has caused new applications of Ethernet. The IEEE 802.3af is mainly a power transformation protocol instead of a data transformation protocol.
The power supply of an Ethernet is started from a power supply equipment. Thus how to use prior art power supply for supply power to this device is a new concern in technology.